Car radios in general are designed to be tuned manually and automatically. A cross arm mechanism is provided particularly for automatic tuning operation, more specifically to predetermine a positional relation between a frequency setting plate and a memory slide plate corresponding to a frequency selected by a manually-operated tuning knob.
The cross arm mechanism includes an arm plate, a frequency setting plate rotatably supported on the arm plate for rotation in response to a movement of a memory slide plate and a plate spring supported on the arm plate for forcibly capturing and locking the frequency setting plate. The arm plate and the plate spring are united together by a pair of pins to prevent relative rotation thereof.
In the prior art mechanism, however, the pins are fixed by caulking and are the same in height. This invites a problem in the assembling process and an increase of the production cost.